Tetramorium shamshir Hita Garcia & Fisher, 2012

Garcia, Francisco Hita & Fisher, Brian L., 2012, The ant genus Tetramorium Mayr (Hymenoptera: Formicidae) in the Malagasy region — taxonomy of the T. bessonii, T. bonibony, T. dysalum, T. marginatum, T. tsingy, and T. weitzeckeri species groups, Zootaxa 3365, pp. 1-123 : 102-105

Tetramorium shamshir Hita Garcia & Fisher sp. n.

(figs 129, 136, 147, 148, 149)

Holotype worker, MADAGASCAR, Antsiranana, Nosy Be, Réserve Naturelle Intégrale de Lokobe , 6.3 km 112° ESE Hellville, 13.41933 S, 48.33117 E, 30 m, rainforest, sifted litter, collection code BLF3422, 19.–24.III.2001 (B.L. Fisher, C. Griswold et al.) ( CASC: CASENT04676969 ) . Paratypes, 32 workers with same data as holotype ( BMNH: CASENT0466635 ; CASENT0466788; CASC: CASENT0466638 ; CASENT0466639; CASENT0466641; CASENT0466645; CASENT0466651; CASENT0466682; CASENT0466683; CASENT0466693; CASENT0466694; CASENT0466700; CASENT0466703; CASENT0466713; CASENT0466741; CASENT0466789; CASENT0466843; CASENT0466874; CASENT0466986; CASENT0466989; CASENT0467027; CASENT0467031; CASENT0467037; CASENT0467055; CASENT0467082; CASENT0467087; CASENT0467093; CASENT0467111; CASENT0467698; MCZ: CASENT0466729; MHNG: CASENT0467056; NHMB: CASENT0466785).

Diagnosis

Tetramorium shamshir is easily recognised within its species group by the following character combination: propodeal spines long to extremely long (PSLI 50–63) and always distinctly curving back; petiolar node thickly cuneiform without being strongly anteroposteriorly compressed dorsally (LPeI 43–53; DPeI 163–184); mesosomal dorsum always with distinct irregular to longitudinal rugulae; body colouration yellow.

Description

HL 0.61–0.75 (0.68); HW 0.56–0.73 (0.65); SL 0.44–0.57 (0.50); EL 0.14–0.17 (0.15); PH 0.30–0.40 (0.36); PW 0.46–0.58 (0.51); WL 0.74–0.94 (0.84); PSL 0.31–0.41 (0.37); PTL 0.12–0.18 (0.15); PTH 0.28–0.35 (0.31); PTW 0.22–0.30 (0.26); PPL 0.19–0.25 (0.21); PPH 0.28–0.35 (0.31); PPW 0.25–0.35 (0.30); CI 93–97 (95); SI 75–82 (82); OI 22–24 (23); DMI 56–68 (60); LMI 40–45 (43); PSLI 50–63 (54); PeNI 48–59 (52); LPeI 43–53 (48); DPeI 163–184 (176); PpNI 54–63 (58); LPpI 64–73 (69); DPpI 125–150 (140); PPI 107–122 (112) (15 measured).

Head longer than wide (CI 93–97). Anterior clypeal margin with median impression. Frontal carinae welldeveloped, ending close to posterior head margin. Antennal scrobes faint and shallow. Antennal scapes short, not reaching posterior head margin (SI 75–82). Eyes of moderate size (OI 22–24). Mesosomal outline in profile flat to weakly convex, strongly marginate from lateral to dorsal mesosoma; promesonotal suture and metanotal groove absent; mesosoma comparatively high, compact, and stout (LMI 40–45). Propodeal spines extremely long, spinose, acute, thick, and always distinctly back-curved (PSLI 50–63); propodeal lobes inconspicuous, very small, and triangular. Petiolar node in profile thickly cuneiform, weakly anteroposteriorly compressed dorsally, rarely node triangular cuneiform and strongly anteroposteriorly compressed dorsally, approximately 1.9 to 2.3 times higher than long (LPeI 43–53), anterior and posterior faces not parallel, anterodorsal margin situated higher than posterodorsal, dorsum moderately tapering backwards posteriorly; node in dorsal view between 1.6 to 1.9 times wider than long (DPeI 163–184). Postpetiole in profile approximately rounded and weakly anteroposteriorly compressed, approximately 1.3 to 1.6 times higher than long (LPpI 64–73), in dorsal view approximately 1.2 to 1.5 times wider than long (DPpI 125–150). Postpetiole in profile less voluminous than petiolar node, in dorsal view approximately 1.1 to 1.2 times wider than petiolar node (PPI 107–122). Mandibles variable, mostly unsculptured, smooth, and shining, often with partly, weak, fine striation, sometimes fully striate; clypeus with one distinct median ruga and one to two weaker and usually shorter rugulae or traces of rugulae laterally; cephalic dorsum between frontal carinae with six to eight longitudinal rugae, rugae mostly unbroken and ending close to posterior head margin, always with one well-developed longitudinal median ruga, median ruga diverging approximately at eye level into two rugae running to posterior clypeal margin, median ruga much shorter than frontal carinae; lateral and ventral head mainly sculptured anteriorly. Ground sculpture on head faint to absent. Mesosoma laterally mostly unsculptured, only sculpture present posteroventrally; dorsal mesosoma with irregular to longitudinal rugulae. Waist segments and gaster unsculptured, smooth, and shiny. All dorsal surfaces of body usually with abundant, long, fine, and erect pilosity, hairs on mesosomal dorsum not restricted to lateral margins. Body of uniform yellow colour.

Notes

This new species is limited in distribution to the northern part of Madagascar. In the northeast, it occurs from Tampolo, Ambanizana, and Nosy Mangabe north to Montagne d'Ambre. To the northwest, it is less common since it is only found in Ampasindava, Manongarivo, and Nosy Be. Tetramorium shamshir is usually encountered in lowland rainforests and littoral rainforests, but rarely in montane or tropical dry forests, which is reflected in its altitudinal range from 5 to 1175 m with an average of 250 m. Furthermore, it seems to be a leaf litter species that is also found in lower vegetation.

Within the T. marginatum group, T. shamshir cannot be mistaken for T. valky , T. hector , T. marginatum , or T. silvicola since the latter four have an unsculptured mesosomal dorsum and are dark brown to black in colour. Tetramorium norvigi , however, shares the yellowish colouration and sculptured mesosomal dorsum of T. shamshir , and both are comparatively close in general habitus. Nevertheless, T. shamshir should not be confused with T. norvigi since they differ significantly in the shape of the propodeal spines and petiolar node. In T. shamshir the spines are always extremely long, very thick, and strongly back-curved (PSLI 50–63), which contrasts with the long, but relatively shorter and thinner spines of T. norvigi (PSLI 37–43). If the spines of the latter are back-curved, they are only weakly so. The petiolar node shape provides further separation since it is thickly cuneiform without being strongly anteroposteriorly compressed dorsally in T. shamshir (LPeI 43–53; DPeI 163–184) while it is triangular cuneiform and strongly anteroposteriorly compressed dorsally in T. norvigi (LPeI 26–41; DPeI 195– 325). In addition, the species also differ in the shape of the postpetiole, which is relatively higher and more strongly anteroposteriorly compressed in T. shamshir (LPpI 64–73; DPpI 125–150) versus more rounded and less anteroposteriorly compressed in T. norvigi (LPpI 78–87; DPpI 116–130).

As already mentioned in the description of T. norvigi , both species occur in sympatry in the region around Anjanaharibe to Marojejy. Nevertheless, the samples from these localities can be discriminated clearly and assigned to either T. norvigi or T. shamshir on the basis of the abovementioned characters. However, several specimens of T. shamshir display a triangular cuneiform and dorsally strongly anteroposteriorly compressed petiolar node in some localities north of Marojejy, and could be mistaken for T. norvigi . Still, the propodeal spines are distinctly back-curved and comparatively thick, which is not common in T. norvigi ; in addition, the latter species does not occur north of Marojejy, making the identification of T. shamshir always straightforward.

Etymology

The species epithet shamshir is derived from "sabre" in Old Persian, and refers to the sabre-like shape of the propodeal spines of the new species. The species epithet is a noun in apposition and thus invariant.

Material examined

MADAGASCAR: Antsiranana, Ambondrobe, 41.1 km 175° Vohemar, 13.71533 S, 50.10167 E, 10 m, littoral rainforest, 29.XI.–1.XII.2004 (B.L. Fisher); Antsiranana, Forêt Ambanitaza, 26.1 km 347° Antalaha, 14.67933 S, 50.18367 E, 240 m, rainforest, 27.XI.2004 (B.L. Fisher); Antsiranana, Ampasindava, Forêt d'Ambilanivy, 3.9 km 181° S Ambaliha, 13.79861 S, 48.16167 E, 600 m, rainforest, 4.–9.III.2001 (B.L. Fisher, C. Griswold et al.); Antsiranana, Res. Ankarana 7 km SE Matsaborimanga, 12° 54' S, 49° 07' E, 150 m, rainforest, 29.XI.1990 (P.S. Ward); Antsiranana, Forêt d'Ampondrabe, 26.3 km 10° NNE Daraina, 12.97 S, 49.7 E, 175 m, tropical dry forest, 11.XII.2003 (B.L. Fisher); Antsiranana, Forêt d'Analabe, 30.0 km 72° ENE Daraina, 13.08333 S, 49.90833 E, 30 m, littoral rainforest, 27.XI.2003 (B.L. Fisher); Antsiranana, Forêt de Binara, 7.5 km 230° SW Daraina, 13.255 S, 49.61667 E, 375 m, tropical dry forest, 1.XII.2003 (B.L. Fisher); Antsiranana, Forêt de Binara, 9.1 km 233° SW Daraina, 13.26333 S, 49.60333 E, 650–800 m, rainforest, 4.XII.2003 (B.L. Fisher); Antsiranana, Forêt de Binara, 9.1 km 233° SW Daraina, 13.26333 S, 49.60333 E, 800 m, rainforest, 20.XI.2004 (B.L. Fisher); Antsiranana, Forêt de Binara, 9.4 km 235° SW Daraina, 13.26333 S, 49.6 E, 1100 m, montane rainforest, 5.XII.2003 (B.L. Fisher); Antsiranana, Forêt de Bekaraoka, 6.8 km 60° ENE Daraina, 13.16667 S, 49.71 E, 150 m, tropical dry forest, 7.XII.2003 (B.L. Fisher); Antsiranana, Nosy Be, Réserve Naturelle Intégrale de Lokobe, 6.3 km 112° ESE Hellville, 13.41933 S, 48.33117 E, 30 m, rainforest, 19.–24.III.2001 (B.L. Fisher, C. Griswold et al.); Antsiranana, Parc National de Marojejy, Manantenina River, 28.0 km 38° NE Andapa, 8.2 km 333° NNW Manantenina, 14.43667 S, 49.775 E, 450 m, rainforest, 12.–15.III.2003 (B.L. Fisher et al.); Antsiranana, Parc National Montagne d'Ambre, 3.6 km 235° SW Joffreville, 12.53444 S, 49.1795 E, 925 m, montane rainforest, 20.–26.I.2001 (B.L. Fisher, C. Griswold et al.); Antsiranana, Réserve Spéciale d'Ambre, 3.5 km 235° SW Sakaramy, 12.46889 S, 49.24217 E, tropical dry forest edge, 325 m, 26.–31.I.2001 (B.L. Fisher, C. Griswold et al.); Antsiranana, R.S. Manongarivo, 12.8 km 228° SW Antanambao, 13.97667 S, 48.42333 E, rainforest, 780 m, 11.X.1998 (B.L. Fisher); Antsiranana, R.S. Manongarivo, 14.5 km 220° SW Antanambao, 13.99833 S, 48.42833 E, montane rainforest, 1175 m, 20.X.1998 (B.L. Fisher); Antsiranana, R.S. Manongarivo, 10.8 km 229° SW Antanambao, 13.96167 S, 48.43333 E, rainforest, 400 m, 8.XI.1998 (B.L. Fisher); Toamasina, 6.9 km NE Ambanizana, Ambohitsitondroina, 15.56667 S, 50 E, 825 m, rainforest, 2.XII.1993 (B.L. Fisher); Toamasina, 6.3 km S Ambanizana, Andranobe, 15.68131 S, 49.958 E, 25 m, rainforest, 14.XI.1993 (B.L. Fisher); Toamasina, 5.3 km SSE Ambanizana, Andranobe, 15.66667 S, 49.96667 E, 425 m, rainforest, 21.XI.1993 (B.L. Fisher); Toamasina, 19 km ESE Maroantsetra, 15° 29' S, 49° 54' E, 250 m, rainforest, 22.IV.1989 (P.S. Ward); Toamasina, Montagne d'Akirindro 7.6 km 341° NNW Ambinanitelo, 15.28833 S, 49.54833 E, 600 m, rainforest, 17.–21.III.2003 (B.L. Fisher, C. Griswold et al.); Toamasina, Montagne d'Anjanaharibe, 18.0 km 21° NNE Ambinanitelo, 15.18833 S, 49.615 E, 470 m, rainforest, 8.–12.III.2003 (B.L. Fisher, C. Griswold et al.); Toamasina, Nosy Mangabe, 18.II.1990 (G.D. Alpert); Toamasina, Nosy Mangabe, 7.43 km S Maroantsetra, 15.4973 S, 49.76223 E, 5 m, littoral rainforest edge, 25.VII.2007 (B.L. Fisher et al.); Toamasina, Tampolo, 40.5 km SSE Maroantsetra, 15.73092 S, 49.95973 E, 18 m, littoral rainforest, 28.VIII.2007 (B.L. Fisher et al.); Toamasina, Tampolo, 39.4 km SSE Maroantsetra 15.70978 S, 49.96965 E, 218 m, disturbed rainforest, 30.VIII.2007 (B.L. Fisher et al.).